A French doctor says men in the delivery room could be making the birth more difficult for their partners.
Obstetrician Michel Odent says fathers could even be responsible for the increase in Caesarean sections.
He says the presence of a male partner in the room makes the woman tense and inhibits her production of oxytocin, the hormone which helps labour.
Odent says this makes women more likely to end up having to have a Caesarean section.
In recent years it has become far more common for the man to be at the birth - but are they doing more harm than good?
Odent is speaking at a debate hosted this week by the Royal College of Midwives.
He told the BBC: "Having been involved for more than 50 years in childbirths in homes and hospitals in France, England and Africa, the best environment I know for an easy birth is when there is nobody around the woman in labour apart from a silent, low-profile and experienced midwife.
"Oxytocin is the love drug which helps the woman give birth and bond with her baby. But it is also a shy hormone and it does not come out when she is surrounded by people and technology. This is what we need to start understanding."
However, Duncan Fisher, a leading advocate for fathers, is arguing against him. He says men are in the delivery room because women want them to be.
Other studies have suggested that having the male partner at the birth is helpful.
In Iran, fathers have recently been allowed into the delivery room because their health ministry wanted to try to reduce the number of Caesarean births.
Patrick O'Brien, a consultant from the Royal College of Obstetricians and Gynaecologists, told the BBC that there were many reasons why the number of emergency Caesarean sections had risen, including obesity, older mothers, and fear of litigation.
He said: "Having a baby together is an intense, life-changing experience that most couples want to experience together. The father can be an immensely reassuring presence for the mother.
"Of course a man shouldn't feel forced to be there, but I have yet to meet one who said after the birth of his baby - 'I wish I'd stayed at home'."
What do you think? Is the man's presence at the birth a help or a hindrance?